Comparison of Paclobutrazol Tablets, Drenches, Gels, Capsules, and Sprays on Chrysanthemum Growth

Abstract

Abstract Paclobutrazol drenches were more effective in retarding chrysanthemum ( Chrysanthemum × morifolium ‘Charm’) plant height than paclobutrazol incorporated in plaster-of-paris tablets, injected hydrogels, and gelatin capsules applied at the same rate (0.5 mg a.i./15-cm pot) in three experiments. Capsules containing paclobutrazol also controlled plant height effectively in all three experiments. Drenches consistently reduced plant area, whereas a 50-ppm paclobutrazol spray did not. Paclobutrazol tablets, gels, and capsules reduced plant area in two of three experiments. Drenches were the only treatment to reduce flower number per plant. Chemical name used: β-[(4-chlorophenyl)methyl]-α-(1,1-dimethylethyl)-1 H -1,2,4-triazole-1-ethanol (paclobutrazol).